Industrial furnaces, such as aluminum furnaces, forging furnaces and the like, typically are fabricated with a surrounding support structure lined with refractory material which may be precast or laid up of refactory tile or brick. One or more access openings are required to allow for interior maintenance, charging of the furnace or other procedures wherein access must be gained to the interior of the furnace. It is a constant problem in the industry to minimize down time during a furnace turnaround. A furnace "turnaround" is a term commonly used to describe the period during which a furnace is repaired, charged or the like.
The access openings to the interior of such furnaces are closed by a door which simply is set in place but which is fabricated of refractory material to protect the surrounding furnace support structure, which may be fabricated of steel, from heat damage. The door should prevent heat leakage past the edges of the door. In addition, with a furnace operating at a positive pressure, it is desirable to eliminate fugitive gas emissions.
The problem of minimizing down time during furnace turnaround is magnified because the surrounding structure, door jambs, lintels, etc. most often are damaged considerably during repairs, charging and other procedures. Minor damage can destroy the door seal system and result in major damage from heat leakage. Major damage can result from mechanical abuse, as by equipment around the access door opening. Consequently, repair or replacement of door jambs and lintels about the furnace access openings is a very frequent problem. It may take as much as a full day to fully repair the refractory framing structure about the access opening and, obviously, this results in expansive down time during the overall furnace turnaround procedures.
This invention is directed to providing a modular door jamb and lintel system for the access door openings of such industrial furnaces to allow for ready replacement thereof and greatly reduce down time during furnace turnaround.